1. Technical Field
Various examples of embodiments may relate to a semiconductor fabricating technology, and more particularly, to a vertical channel type nonvolatile memory device and a fabricating method thereof.
2. Related Art
A memory device may be classified into either a volatile memory device or a nonvolatile memory device according to whether data is retained when power to the device is interrupted. The volatile memory device is a memory device in which data is lost when power is off or is interrupted to the device, and includes a DRAM, a SRAM and the like. The nonvolatile memory device is a memory device in which stored data is retained although power is off or is interrupted to the device, and includes a flash memory device and the like.
Recently, the degree of integration of a flat type nonvolatile memory device is not sufficient. To improve the degree of integration for a memory device there has been proposed a vertical channel type nonvolatile memory device in which strings are arranged vertically from a substrate. The vertical channel type nonvolatile memory device has a structure in which a lower selection transistor, a plurality of conductive layers, and an upper selection transistor are sequentially stacked on the substrate. This structure improves the degree of integration of a memory device through the strings arranged vertically from the substrate.